FBA Storage Fee Calculator

About the FBA Storage Fee Calculator

The FBA Storage Fee Calculator estimates your monthly Amazon FBA storage costs based on the cubic feet your inventory occupies. Amazon charges storage per cubic foot per month, with standard rates of $0.87/cu ft (January–September) that spike to $2.40/cu ft during peak season (October–December).

Storage fees are one of the most commonly overlooked costs for Amazon sellers. Slow-moving inventory can accumulate significant charges: a product occupying 1 cubic foot that sits for 6 months costs $5.22 in standard-season storage alone. Items stored over 181 days incur additional aged inventory surcharges.

This calculator helps you estimate total storage costs based on your inventory quantity, product dimensions, and the time of year. Use it to optimize inventory levels, identify products with unsustainable storage costs, and plan inbound shipments to avoid excess stock during expensive Q4 storage.

When This Page Helps

FBA storage fees silently eat margins, especially during Q4 when rates nearly triple. This calculator shows the real cost of holding inventory at Amazon so you can optimize stock levels and avoid aged inventory surcharges.

How to Use the Inputs

1. Enter the product dimensions (length, width, height).
2. Enter the quantity of units currently stored.
3. Select the season (standard or Q4 peak).
4. Enter the average days in storage for aged inventory surcharge check.
5. View the monthly storage cost total and per-unit breakdown.

Example Calculation

Tips & Best Practices

• Reduce inventory to 30–45 days of supply before October to minimize Q4 storage costs.
• Products with a storage cost per unit above 5% of selling price need inventory optimization.
• Use Amazon's Inventory Performance Index (IPI) to avoid storage limits and overage fees.
• Consider removing slow-selling inventory before it hits the 181-day aged inventory threshold.
• Ship smaller, more frequent inbound shipments to keep inventory lean.
• Products that sell 1+ units/day should have no more than 60–90 days of supply at FBA.

FBA Storage Fee Schedule

Standard-size items: $0.87/cu ft (Jan–Sep), $2.40/cu ft (Oct–Dec). Oversize items: $0.56/cu ft (Jan–Sep), $1.40/cu ft (Oct–Dec). Dangerous goods: $0.99/cu ft (Jan–Sep), $3.63/cu ft (Oct–Dec). All rates are per calendar month based on average daily inventory volume.

Aged Inventory Surcharges

Items stored 181–210 days: $0.50/cu ft or $0.10/unit (whichever is greater). 211–240 days: $1.00/cu ft. 241–270 days: $1.50/cu ft. 271–300 days: $3.80/cu ft. 301–330 days: $4.00/cu ft. 331–365 days: $5.45/cu ft. Over 365 days: $6.90/cu ft or $0.15/unit.

Storage Cost as Part of Total FBA Cost

For a typical product selling 2 units/day with 60 days of supply, storage is 2–5% of total FBA cost. But for slow-selling products (1 unit/week with 90 days supply), storage can reach 15–25% of total cost. Always factor storage into your per-unit profitability calculation.

Frequently Asked Questions

• How are FBA storage fees calculated?

  Amazon measures the cubic feet your inventory occupies daily and charges monthly based on the average daily volume. Rates are $0.87/cu ft (Jan–Sep) and $2.40/cu ft (Oct–Dec) for standard-size items. Oversize items are charged $0.56/cu ft and $1.40/cu ft respectively.

• What is the aged inventory surcharge?

  Items stored at FBA for over 181 days incur an aged inventory surcharge (formerly called long-term storage fees). The surcharge starts at $0.50/cu ft for 181–210 days and increases with age, up to $6.90/cu ft for items over 365 days. This is charged on top of regular monthly storage.

• How can I reduce FBA storage fees?

  Send smaller inbound shipments more frequently, remove slow-selling inventory before it ages, run promotions to increase sell-through rate, and reduce Q4 inventory to essential stock only. Monitor the Inventory Performance Index (IPI) to maintain your storage allocation.

• Why do Q4 storage fees increase so much?

  Amazon increases October–December rates because warehouse space is at a premium during the holiday season. The rate jumps from $0.87 to $2.40/cu ft (2.75× increase). Sellers should reduce non-essential inventory before October and prioritize fast-selling holiday items.

• Is it cheaper to store inventory myself?

  Self-storage in a warehouse or garage typically costs $0.50–2.00/sq ft per month, which translates to much less per cubic foot than FBA. However, you lose FBA shipping benefits and Prime eligibility. The best approach is keeping lean FBA inventory and storing bulk stock yourself.

• What is the Inventory Performance Index (IPI)?

  The IPI is Amazon's score (0–1000) that measures how well you manage FBA inventory. Scores below 400 result in storage limits and overage fees. Improve your IPI by fixing stranded inventory, improving sell-through rate, and reducing excess stock.